package com.brainmaster.apps.invoicing.data;

import com.brainmaster.apps.invoicing.model.Member;

import java.util.List;
import javax.annotation.PostConstruct;
import javax.enterprise.context.RequestScoped;
import javax.enterprise.event.Observes;
import javax.enterprise.event.Reception;

import javax.enterprise.inject.Produces;
import javax.inject.Inject;
import javax.inject.Named;
import javax.persistence.EntityManager;
import javax.persistence.criteria.CriteriaBuilder;
import javax.persistence.criteria.CriteriaQuery;
import javax.persistence.criteria.Root;

@RequestScoped
public class MemberListProducer {
    @Inject
    private EntityManager em;

    private List<Member> members;

    // @Named provides access the return value via the EL variable name
    // "members" in the UI (e.g.,
    // Facelets or JSP view)
    @Produces
    @Named
    public List<Member> getMembers() {
	return members;
    }

    public void onMemberListChanged(
	    @Observes(notifyObserver = Reception.IF_EXISTS) final Member member) {
	retrieveAllMembersOrderedByName();
    }

    @PostConstruct
    public void retrieveAllMembersOrderedByName() {
	CriteriaBuilder cb = em.getCriteriaBuilder();
	CriteriaQuery<Member> criteria = cb.createQuery(Member.class);
	Root<Member> member = criteria.from(Member.class);
	// Swap criteria statements if you would like to try out type-safe
	// criteria queries, a new
	// feature in JPA 2.0
	// criteria.select(member).orderBy(cb.asc(member.get(Member_.name)));
	criteria.select(member).orderBy(cb.asc(member.get("name")));
	members = em.createQuery(criteria).getResultList();
    }
}
